Fuse



' No Drawing.

Patented Nov. 10,

UNITED STATES PATENT OFFICE.

WALTER O. SNELLING, OF ALLENTOWN, PENNSYLVANIA. ASSIGNOR TO TROJAN POWDER COMPANY,-OF NEW YORK, N. -Y., A CORPORATION OF NEW YORK.

FUSE.

To all whom it may concern.

Be it known that I, WALTER O. SNELLING, a citizen of'the United States, residing in Allentown, Lehigh County, Pennsylvania,

have invented -certain Improvements in Fuses, of which the following is a specification.

My invention relates .to improvements in fuse, and the principal object of .the invention is to provide an improved fuse for mining and quarrying use.

Fuse of the type commonly employed in mining and quarrying comprises a central core or train of powder surrounded by wrappings of cord or tape and waterproofed by layers of tar, guttapercha or like materials. In use, there is frequently a considerable length of the fuse in contact with the explosive in thebore hole before it reaches the deton'ating cap, and because of the common tendency of ordinary fuse to burn through the sides or to exude hot tar or other waterproofing material at a temperature in excess of the ignition temperature of the explosive, it frequently happens that the charge of explosive in a bore hole seton fire by the fuse before the tram of powder in the core has transmltted inflammation to the detonator or cap.

The principal object of my present 111- vention is to provide a fuse which will be free from this tendency to ignite powder either by projecting flame or hot gases. or

by exuding through'the sides of the fuse hot tarry-or other waterproofing materials.

I have discovered that by employing, instead of the usual. waterproofing materials, a'mixture comprisin an unvulcanized but I vulcanizable materia', I am able to materially modifyor entirely eliminate the aforedescribedtside spitting tendency of .fuse with its attendant objectionableness.

By vulcanizable-material I mean one which upon being heated will develop a change in ph sical characteristics tending towards solidi cation, or will' become less fluid rather than more fluid.- By vulcanization is meant the (process of becoming less, fluid or more with increasing temperature 1n eonmaterials.

In the 'praeti of my invention, I may employ many materials as the waterproofing Application filed March 2, 1925. Serial No. 12,795.

agent, although I prefer to employ mixtures comprlsing rubber and sulfur, or gutt-a I made in accordance with my invention, I may employ a-coating consisting of a mixture of asphalt, tar or like material with unvulcanized rubber and sulfur, preferably in assoc ation with an accelerator ot' vulcanization for the purpose of causing the vulcanlzmg reaction to go on at a lower temperature. The amount of rubber present in the tar-asphalt composition may be comparatively small, for example from to'207}, and there should be sutlicien't. sulfur to vulcanize this rubber and to leave a considerable excess for the tar-asphalt composition. As examples of accelerators of vulcanization that may be successfully employed, I may use hexamethylenetetramine,v quinoline, piperidine, &c., and the accelerator may be present in amount up say to 1% oflthe composition, the amount being determined by the rapiditywith which it is desired that the vulcanization take. place. It should be understood, however, that the accelerator may be entirely omitted and I wish to place scribed a 'vulcanizable material requiring for vulcanization the presence of a vulcanizing agent, it will beunderstood that I do I not limit'myself tothisparticular class of vulcanizable' materiaL- I may employ forexample Such materials as tung oil, com

monly knfown as China wood oil, ,whichhardens when heated, and this material can replace a m'ixture of rubber and sulfur in the waterproofing compound; It is also well known that phenol formaldehyde condensation products, such as bakelite varnish,

harden on the application of heat, and resins of this type have been used with success ,as waterproofing agents in connection with the powder core burns, however, the intense heat thus produced exceeds the vulcanization temperature of the rubber sulfur mixture or other vulcanizable agent in the waterproofin composition, and the vulcanization of this material forms a solid body that holds together the other constituents of the composition and prevents the throwing off or exuding of these constituents from the fuse.

I-have found that it is of material aSs1st ance in the application of my invention to employ wrappmgs of paper around my waterproofing composition and inside the final countering of my fuse. I preferably employ one wrapping of paper in the form of a tube of paper, the two edges of the,

paper being slightlyjoverlapped, and a second wrapping of paper in the formof a spiral wrapping. may place any waterproofing agent within the innermost of the two paper wrappings, or-I may place my waterproofing agent between the two wrappings.

I claim:

1.;Fuse comprising a powder core, and a waterproofing cover for said core including a substance tending to vulcanize with increasing temperature. I

'2. Fuse comprising a-rpowder'core, and a waterproofingcover forsaid core including an unvulcanizedvulcanizable material.

3. Fuse comprising. a powder core, and a bitumen waterproofing cover comprising an unvulcanized vulcanizable material.

v4:. Fuse comprising a powder core, and a waterproofing cover for said core including an unvulcanized vulcanizablematerial and a vulcanizing agent. 7 1

15. Fuse comprising a powder'core, and a protective cover for said core comprising unvulcanized rubber and a vulcanizing agent.

. 6. Fuse comprising a powder core, and a protective cover for the core comprising an unvulcanized vulcanizable material, a vulcanizmg agent, and a vulcanization accelerator.

7. Fuse comprising a powder core, and a rotect-ive cover for said core including hina wood oil.

8. Fuse comprising a powder core, and a protective cover for said core including an unhardened synthetic resin.

9. A waterproof coating material for fuse comprising an unvulcanized 'vulcanizable material.

10. A coating material for fuse comprising a plastic waterproofing substance in admixture with an unvulcanized vulcanizable material.

11. A coating material for fuse comprising a plastic bitumen substance containing an unvulcanized vulcanizable material.

12.. A coating material for fuse comprismg a plastic waterproofing substance, unvulcanized rubber and sulfur.

13. A coating material for fuse comprising a plastic waterproofing substance, unvulcanized rubber, and sulfur in excess of the amount required to Vulcanize the said rubber.

14. A coating material for fuse comprism a plastic waterproofin substance conta1ning 5% to 20% of unvulcanized rubber, and sulfur in excess of the amount required to vulcanize said rubber.

15. A coating material for fuse comprising unvulcanized rubber and sulfur.

16. A coating. material-for fuse comprismg unvulcanized rubber and sulfur in excess of the amount required to vulcanizesaid rubber.

17. A coating material for fuse compris- -ing an unvulcanized vulcanizable material and a vulcanizing agent. i t 18. A coat ng materialfor fuse comprising a vulcanizable material and a vulcanization accelerator. .19. A coating material for fuse comprising unvulcanized rubber, sulfur and hexamethylenetetramine. 20. A coating material for fuse comprising an unvulcanized vulcanizable material, a

vulcamzing agent, and avulcanization ac-.

celerator.

21. A. coating material for fuse comprising China-wood oil. 7

22. A coating material for fuse comprising an unhardened synthetic resin.

23. The method of manufacturing fuse, which consists in taking a powder core and covering said core with a waterproofing material including an unvulcanized vulcanizable material.

24. The method of preventing sidespittin in fuse comprising a waterproof cover, which consists in incorporating in said cover an unvulcanized vulcanizable material.

25. The method of manufacturing fuse which consists in preparing a waterproofing material containing an unvulcanized vulcanizable material, heating the material to a liquid or plastic condition at a temperature below that required for vulcanizatlon, and applying thematerial to a powder core in the form of a protective cover.

' WALTER o. sNELLING. 

